At present, as more people use wireless local area networks (WLANs) for data communication, WLAN load has been constantly aggravated. Moreover, as the number of WLAN users increases, efficiency of data communication using the WLANs will decrease significantly as well. In such case, the problem of decrease of the efficiency of data communication using the WLANs cannot be prevented to occur purely by improving data rate of the WLANs.
Therefore, the IEEE standards organization establishes the related task groups to engage in resolving the problem of the efficiency of the WLANs. Multi-user data transmission, as one of alternative technologies to resolve the efficiency of the networks, has aroused wide attention and research. At present, the parallel multi-user data transmission technology studied by the HEW group includes spatial domain multiple access, i.e., multi-user multi-input multi-output (MU-MIMO) technology, frequency domain multiple access, i.e., orthogonal frequency division multiple access technology (OFDMA) and code division domain multiple access, i.e., interleave division multiple access technology.
FIG. 1 is a schematic diagram of a basic service set in the WLANs. As shown in FIG. 1, in the WLANs, an access point (AP) and a plurality of non-access point station (non-AP STA) associated with the AP compose a basic service set (BSS). Typically, the parallel multi-user data transmission mentioned in the WLANs means that a plurality of secondary nodes send data to a primary node simultaneously, and is also referred to as an uplink multi-user data transmission, or means that a primary node send data to a plurality of secondary nodes simultaneously, and is also referred to as a downlink multi-user data transmission. The primary node typically refers to an AP or a non-AP STA with special ability, and the secondary node typically refers to a non-AP STA.
It can be seen from the above analysis that the uplink multi-user data transmission used by the WLANs is the parallel multi-user data transmission, and can improve effectively the efficiency of the WLANs. However, at present in the related art, specific technical schemes for implementing the parallel multi-user data transmission have not been provided yet, and the response and paging of successive multi-user multi-frame transmission cannot be achieved either. That is, there are still many problems to be solved, such as, how does the AP respond to data of multiple uplink users; how to avoid interference between the uplink multi-user data transmissions, and synchronization between multi-user data transmissions; and how to reduce competitive overhead of multi-user transmission, and how to achieve uplink multi-user multi-frame transmission after one success of competition.
In summary, the related art cannot ensure implementation of the parallel multi-user data transmission in the WLANs.